Hydrogen as an Energy Carrier: What It Is and Why It Matters

Last week, the U.S. Department of Energy announced it would make available up to $ 9 million in new funding to accelerate the development of hydrogen and fuel cell technologies for use in vehicles, backup power systems, and hydrogen refueling components. These investments aim at strengthening U.S. leadership in cost-effective hydrogen and fuel cell technologies, and will help the industry introduce hydrogen technologies to the market at lower cost.

What is hydrogen and why does it require significant R&D investment? This blog post aims to answer these critical questions.

Introduction to hydrogen and fuel cells

Hydrogen is the lightest and most abundant element in the universe. It accounts for 74% of all nuclear matter and together with oxygen constitutes water molecules. Hydrogen can be produced through various methods such as steam reforming, (photo-)electrolysis and thermolysis. Unlike coal, crude oil or natural gas, it is not a primary energy source but an energy carrier, comparable to electricity. It can be converted into usable energy by means of combustion or, most commonly, an electrochemical process in fuel cells. A fuel cell is a device in which chemical energy from a fuel like hydrogen is directly converted into electricity through a chemical reaction with oxygen.

What makes hydrogen so unique?

For the U.S. to achieve its long-term air pollution, climate change and energy security goals, it is essential to develop next-generation energy sources that are clean and abundant. Hydrogen can help because its conversion into electricity does not emit greenhouse gases, but only heat and water as by-products, hydrogen is a unique zero-emission energy carrier. In a fuel cell, this process is 2-3 times more efficient than in an internal combustion engine. Sustainable energy sources able to produce hydrogen include fusion, solar, wind, and hydropower, as well as biomass and photosynthesis (green algae).

The currently popular fossil fuel driven Hybrid Electric Vehicles and Plug-in Hybrid Electric Vehicles are a good example of technological advancements on the market, but these vehicles still make use of internal combustion engines which emit greenhouse gases and depend on electricity that is primarily produced from fossil fuels. Hydrogen-driven Fuel Cell Electric Vehicles however, as the figure below shows, do have the potential of cutting U.S. greenhouse gas emissions to 80% below 1990 levels because of their ultraclean energy conversion process.

‘Projected greenhouse gases for different alternative vehicle scenarios over the 21st century for the U.S. light duty vehicle fleet, assuming that both the electrical grid and hydrogen production reduce their carbon footprints over time (BEV= battery electric vehicle; H2 ICE HEV = hydrogen internal combustion engine hybrid electric vehicle)’ Source: H2Gen Innovations

Revolutionary military and commercial applications

Hydrogen has the potential to provide revolutionary advantages through both military and large-scale commercial applications. For the military, it can provide the tactical advantage of reducing the weight burden for a standard 72-hour mission profile of 24 lbs. in batteries to only 9.5 lbs. in fuel cell power systems, a 60% reduction. This reduces physical stress and increases power flexibility of troops. The utilization of hydrogen can also significantly extend the reach of unmanned aerial, undersea and ground vehicles, while reducing noise and heat signatures, and enabling ‘silent watch’ operations.

For commercial application, hydrogen fueled vehicles have a driving range of 350 miles, whereas battery electric vehicles only reach up to 200 miles. Hydrogen fuel cells help overcome the hurdles that battery electric vehicles have: battery replacement and irreversible capacity loss. Furthermore, it introduces the revolutionary concept of peer-to-peer energy sharing because of the possibility of transferring to and from electricity. This is an energy system that allows society the vast possibilities of decentralized electricity redistribution. To provide an example: a hydrogen fueled car could be plugged into a home or office to function as a power station with an energy generation capacity of 20 kilowatts, to provide and sell premium electricity to the interactive grid. Instead of having cars merely occupy space, hydrogen fuel cell technology can turn them into profit centers. According to environmental scientist Amory Lovins, the U.S. hydrogen fueled ‘Hypercar’ fleet will ultimately total 3-6 terawatts, which is 5-10 times the total generating capacity of the national grid.

Hydrogen is a sustainable next-generation energy carrier with the option for unique zero-emission and highly efficient energy conversion. It has the potential to drastically improve military tactical capabilities and introduces revolutionary large-scale commercial applications that will enable us to vastly redistribute energy.

Major barriers to the cost-effective market entry of hydrogen technology include the high R&D and infrastructural change expenditure. The U.S. Department of Energy set-up a Hydrogen and Fuel Cells Program  which works together with industry, academia, and national laboratories, as well as federal and international agencies to overcome such barriers. These joint-efforts are exemplary in achieving a higher public awareness of imminent energy issues and will bring us a step closer to transitioning our energy economies in a sustainable and clean way.

Kareem Chin is an Adjunct Junior Fellow at the American Security Project, a non-partisan think tank devoted to studying questions of America’s long-term national security. He is a master’s candidate in CEMS International Management at the Rotterdam School of Management, Erasmus University in the Netherlands, and in Military Strategic Studies at the Netherlands Defense Academy.

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